The hall for celebrations, the Small Hall, has one of the most luxurious interiors in the otherwise ascetic building. It is an important place in the University history because the ceremonious opening of the University took place exactly in the Small Hall on 28 September, 1919. The Small Hall was created already in the time of the construction of the first building and the author of its interior is architect Gustav Hilbig. A luxurious chandelier and three large windows provide lighting in the hall – at first the windows were adorned with stained glass which has not preserved until the present day. Figurative mouldings play an important role in this interior of the Renaissance style. Twenty eight decorative mouldings have been placed in the double semi-circle and pointed arch frames symbolically depicting the mythical characters of the ancient city of Rome associated with the legend of the twin brothers Romulus and Remus. The story about the creation of Rome and its development is depicted in a concisely symbolical and artistic manner pointing to the then perceived parallels with Riga that flowered in the 19th century. The human, bird and animal shapes in the mouldings are often created from a stylized twine of leaves and flowers. The bottom edge of the wall cornice in its whole length is decorated by a stylized ornament of acanthus leaves.

In 1928, architect Eižens Laube (1880-1967) added a two-stage platform to the interior of the Small Hall. It is notable that Eižens Laube usually formed the design of objects so that they would meet the overall character of the building and would be unique without possibilities of duplication. After the creation of the platform an unwritten law came about – during the ceremonial events only the president of the State and the rector of the University of Latvia could speak to the audience from the highest part of the platform, while anyone could speak from the lower part. Above the platform there was the National Emblem of the Republic of Latvia, which was sawed off and destroyed during the Soviet times. The emblem was recreated in honour of the 75th anniversary of the University of Latvia.